document_title: Alexander the Great in the Quran

question_text: who is the servant through whom allah provided the quran

question_tokens: who is the servant through whom allah provided the quran

root

text: Alexander the Great in the Quran

text: Historical background on religious Alexander legends[edit]

text: There have been many different cultural depictions of Alexander the Great since antiquity, including references in the Hebrew Bible in 1 Maccabees and the Book of Daniel. Alexander the Great was an immensely popular figure in the classical and post-classical cultures of the Mediterranean and Middle East. Almost immediately after his death in 323 BC a body of legend began to accumulate about his exploits and life which, over the centuries, became increasingly fantastic as well as allegorical. Collectively this tradition is called the Alexander romance and some recensions feature such vivid episodes as Alexander ascending through the air to Paradise, journeying to the bottom of the sea in a glass bubble, and journeying through the Land of Darkness in search of the Water of Life (Fountain of Youth).

tag: p

text: The earliest Greek manuscripts of the Alexander romance, as they have survived, indicate that it was composed at Alexandria in the 3rd century. The original text was lost but was the source of some eighty different versions written in twenty-four different languages.[4] As the Alexander romance persisted in popularity over the centuries, it was assumed by various neighboring people. Of particular significance was its incorporation into Jewish and later Christian legendary traditions. In the Jewish tradition Alexander was initially a figure of satire, representing the vain or covetous ruler who is ignorant of larger spiritual truths. Yet their belief in a just, all-powerful God forced Jewish interpreters of the Alexander tradition to come to terms with Alexander's undeniable temporal success. Why would a just, all-powerful God show such favor to an unrighteous ruler? This theological need, plus acculturation to Hellenism, led to a more positive Jewish interpretation of the Alexander legacy. In its most neutral form this was typified by having Alexander show deference to either the Jewish people or the symbols of their faith. In having the great conqueror thus acknowledge the essential truth of the Jews' religious, intellectual, or ethical traditions, the prestige of Alexander was harnessed to the cause of Jewish ethnocentrism. Eventually Jewish writers would almost completely co-opt Alexander, depicting him as a righteous gentile or even a believing monotheist.[5]

text: The Christianized peoples of the Near East, inheritors of both the Hellenic as well as Judaic strands of the Alexander romance, further theologized Alexander until in some stories he was depicted as a saint. The Christian legends turned the ancient Greek conqueror Alexander III into Alexander "the Believing King", implying that he was a believer in monotheism. Eventually elements of the Alexander romance were combined with Biblical legends such as Gog and Magog.

text: During the period of history during which the Alexander romance was written, little was known about the true historical Alexander the Great as most of the history of his conquests had been preserved in the form of folklore and legends. It was not until the Renaissance (1300–1600 AD) that the true history of Alexander III was rediscovered:

text: Since the death of Alexander the Great in 323 BC there has been no age in history, whether in the West or in the East, in which his name and exploits have not been familiar. And yet not only have all contemporary records been lost but even the work based on those records though written some four and a half centuries after his death, the Anabasis of Arrian, was totally unknown to the writers of the Middle Ages and became available to Western scholarship only with the Revival of Learning [the Renaissance]. The perpetuation of Alexander's fame through so many ages and amongst so many peoples is due in the main to the innumerable recensions and transmogrifications of a work known as the Alexander Romance or Pseudo-Callisthenes.[6]

text: Dating and origins of the Alexander legends[edit]

text: The legendary Alexander material originated as early as the time of the Ptolemaic dynasty (305 BC to 30 BC) and its unknown authors are sometimes referred to as the Pseudo-Callisthenes (not to be confused with Callisthenes of Olynthus, who was Alexander's official historian). The earliest surviving manuscript of the Alexander romance, called the α (alpha) recension, can be dated to the 3rd century AD and was written in Greek in Alexandria:

text: There have been many theories regarding the date and sources of this curious work [the Alexander romance]. According to the most recent authority, ... it was compiled by a Greco-Egyptian writing in Alexandria about A.D. 300. The sources on which the anonymous author drew were twofold. On the one hand he made use of a `romanticized history of Alexander of a highly rhetorical type depending on the Cleitarchus tradition, and with this he amalgamated a collection of imaginary letters derived from an Epistolary Romance of Alexander written in the first century B.C. He also included two long letters from Alexander to his mother Olympias and his tutor Aristotle describing his marvellous adventures in India and at the end of the World. These are the literary expression of a living popular tradition and as such are the most remarkable and interesting part of the work.[8]

text: The Greek variants of the Alexander romance continued to evolve until, in the 4th century, the Greek legend was translated into Latin by Julius Valerius Alexander Polemius (where it is called the Res gestae Alexandri Magni) and from Latin it spread to all major vernacular languages of Europe in the Middle Ages. Around the same as its translation into Latin, the Greek text was also translated into the Syriac language and from Syriac it spread to eastern cultures and languages as far afield as China and Southeast Asia.[9] The Syriac legend was the source of an Arabic variant called the Qisas Dhul-Qarnayn (Tales of Dhul-Qarnayn)[10] and a Persian variant called the Iskandarnamah (Book of Alexander), as well as Armenian and Ethiopic translations.[11]

text: The version recorded in Syriac is of particular importance because it was current in the Middle East during the time of the Quran's writing and is regarded as being closely related to the literary and linguistic origins of the story of Dhul-Qarnayn in the Quran. The Syriac legend, as it has survived, consists of five distinct manuscripts, including a Syriac Christian religious legend concerning Alexander and a sermon about Alexander attributed to the Syriac poet-theologian Jacob of Serugh (451–521 AD, also called Mar Jacob). The Syriac Christian legend concentrates on Alexander's journey to the end of the World, where he constructs the Gates of Alexander to enclose the evil nations of Gog and Magog, while the sermon describes his journey to the Land of Darkness to discover the Water of Life (Fountain of Youth). These legends concerning Alexander are remarkably similar to the story of Dhul-Qarnayn found in the Quran.[12]

text: One of the five Syriac manuscripts, dated to the 18th century, has a version of the Syriac legend that has been generally dated to between 629 AD and 636 AD. There is evidence in the legend of "ex eventu knowledge of the Khazar invasion of Armenia in A.D. 629,"[13][14] which suggests that the legend must have been burdened with additions by a redactor sometime around 629 AD. The legend appears to have been composed as propaganda in support of Emperor Heraclius (575–641 AD) shortly after he defeated the Persians in the Byzantine-Sassanid War of 602–628. It is notable that this manuscript fails to mention the Islamic conquest of Jerusalem in 636 AD by Muhammad's (570–632 AD) successor, Caliph Umar (590–644 AD). This fact means that the legend might have been recorded before the "cataclysmic event"`that was the Muslim conquest of Syria and the resulting surrender of Jerusalem in November 636 AD. That the Byzantine–Arab Wars would have been referenced in the legend, had it been written after 636 AD, is supported by the fact that in 692 AD a Syriac Christian adaption of the Alexander romance called the Apocalypse of Pseudo-Methodius was indeed written as a response to the Muslim invasions and was falsely attributed to St Methodius (?–311 AD); this Apocalypse of Pseudo-Methodius equated the evil nations of Gog and Magog with the Muslim invaders and shaped the eschatological imagination of Christendom for centuries.[12]

text: The manuscripts also contain evidence of lost texts. For example, there is some evidence of a lost pre-Islamic Arabic version of the translation that is thought to have been an intermediary between the Syriac Christian and the Ethiopic Christian translations.[15] There is also evidence that the Syriac translation was not directly based on the Greek recensions but was based on a lost Pahlavi (pre-Islamic Persian) intermediary.[8]

text: Theological controversy[edit]

text: The identity of Dhul-Qarnayn has been a matter of theological controversy amongst Muslim scholars for centuries. Dhul-Qarnayn was equated with Alexander by the majority of classical Islamic scholars during a period when Christians and Jews had themselves co-opted Alexander the Great as a religious figure. However, it is clear that the historical Alexander the Great was a Greek pagan (for example, Alexander's mother Olympias is said to have been a devout member of the orgiastic snake-worshiping cult of Dionysus, and may have slept with snakes[16]). Such historical facts about Alexander the Great became well known only after the Renaissance period (1300–1600 AD) when the Anabasis Alexandri of Arrian (AD 86–160) was rediscovered. In light of the modern view of Alexander the Great, his identity as Dhul-Qarnayn has become a matter of great controversy for Muslims. In reaction, alternative theories about the identity of Dhul-Qarnayn have been advanced by some Muslim scholars. For example, it has been suggested that Dhul-Qarnayn could be Cyrus the Great (see Cyrus the Great in the Quran). The Muslim sentiment against Alexander is reflected in Islamic textbooks (e.g. "Some [Muslim Scholars] say it was Alexander the Great, who lived from 356 BCE to 323 BCE, but that is highly unlikely, given that Alexander was an idol-worshipper."[17]), often with references to his polytheistic religious beliefs and (more recently) his personal relationships.

text: Dhul-Qarnayn in Islamic literature[edit]

text: Quran[edit]

text: "Dhul-Qarnayn" (the "Two-Horned One" in English) is a person described in the Quran, the sacred scripture believed by Muslims to have been revealed by Allah to Muhammad. The story of Dhul-Qarnayn appears in seventeen short verses of the Quran, specifically verses 18:83–99 of Surah Al-Kahf. Dhul-Qarnayn is mentioned in only one place in the Quran, unlike the more familiar stories that are repeated throughout the text (for example, Jesus is mentioned in 93 verses in 15 different surahs of the Quran). The Quranic story describes a man called Dhul-Qarnayn (meaning "the Two-Horned"), who was already familiar to the inhabitants of the region, to whom Allah gave great power, and who traveled to a place, where it appeared to him as if the sun was setting in a murky (or boiling) sea. At this place, Dhul-Qarnayn builds a wall in order to enclose the nations of Gog and Magog. It is thought that Gog and Magog will breach Dhul-Qarnayn's wall before Yaum al-Qiyāmah (the Day of Judgement) and will wreak havoc in the world (Islamic Armageddon):

text:
Quran Verse
Abdullah Yusuf Ali
Pickthall

18:83
They ask thee concerning Zul-qarnain Say, "I will rehearse to you something of his story."
They will ask thee of Dhu'l-Qarneyn. Say: "I shall recite unto you a remembrance of him."

18:84
Verily We established his power on earth, and We gave him the ways and the means to all ends.
Lo! We made him strong in the land and gave him unto every thing a road.

18:85
One (such) way he followed,
And he followed a road

18:86
Until, when he reached the setting of the sun, he found it set in a spring of murky water: near it he found a people: We said: "O Zul-qarnain! (thou hast authority), either to punish them, or to treat them with kindness."
Till, when he reached the setting-place of the sun, he found it setting in a muddy spring, and found a people thereabout. We said: "O Dhu'l-Qarneyn! Either punish or show them kindness."

18:87
He said: "Whoever doth wrong, him shall we punish; then shall he be sent back to his Lord; and He will punish him with a punishment unheard-of (before).
He said: "As for him who doeth wrong, we shall punish him, and then he will be brought back unto his Lord, Who will punish him with awful punishment!"

18:88
"But whoever believes, and works righteousness, he shall have a goodly reward, and easy will be his task as we order it by our command."
"But as for him who believeth and doeth right, good will be his reward, and We shall speak unto him a mild command."

18:89
Then followed he (another) way.
Then he followed a road

18:90
Until, when he came to the rising of the sun, he found it rising on a people for whom We had provided no covering protection against the sun.
Till, when he reached the rising-place of the sun, he found it rising on a people for whom We had appointed no shelter therefrom.

18:91
(He left them) as they were: We completely understood what was before him.
So (it was). And We knew all concerning him.

18:92
Then followed he (another) way.
Then he followed a road

18:93
Until, when he reached (a tract) between two mountains, he found, beneath them, a people who scarcely understood a word.
Till, when he came between the two mountains, he found upon their hither side a folk that scarce could understand a saying.

18:94
They said: "O Zul-qarnain! the Gog and Magog (people) do great mischief on earth: shall we then render thee tribute in order that thou mightest erect a barrier [wall] between us and them?"
They said: "O Dhu'l-Qarneyn! Lo! Gog and Magog are spoiling the land. So may we pay thee tribute on condition that thou set a barrier [wall] between us and them?"

18:95
He said: "(The power) in which my Lord has established me is better (than tribute): help me therefore with strength (and labour): I will erect a strong barrier [wall] between you and them:
He said: "That wherein my Lord hath established me is better (than your tribute). Do but help me with strength (of men), I will set between you and them a bank [wall]."

18:96
"Bring me blocks of iron." At length, when he had filled up the space between the two steep mountain sides, he said, "Blow (with your bellows)" then, when he had made it (red) as fire, he said: "Bring me, that I may pour over it, molten lead."
"Give me pieces of iron" – till, when he had leveled up (the gap) between the cliffs, he said: "Blow!" – till, when he had made it a fire, he said: "Bring me molten copper to pour thereon."

18:97
Thus were they made powerless to scale it or to dig through it.
And (Gog and Magog) were not able to surmount, nor could they pierce (it).

18:98
He said: "This is a mercy from my Lord: but when the promise of my Lord comes to pass, He will make it into dust; and the promise of my Lord is true."
He said: "This is a mercy from my Lord; but when the promise of my Lord cometh to pass, He will lay it low, for the promise of my Lord is true."

18:99
On that day We shall leave them [Gog and Magog] to surge like waves on one another: the trumpet will be blown, and We shall collect them all together.
And on that day we shall let some of them [Gog and Magog] surge against others, and the Trumpet will be blown. Then We shall gather them together in one gathering.

tag: table

text: Sira[edit]

text: The earliest mention of Dhul-Qarnayn outside the Quran is found in the works of the earliest Muslim historian and hagiographer, Ibn Ishaq (?–761 AD), which form the main corpus of the Sira (religious biography) literature. Ibn Ishaq's Sira reports that the eighteenth chapter of the Quran (which includes the story of Dhul-Qarnayn) was revealed to Muhammad by God on account of some questions posed to Muhammad by the rabbis. The verse was revealed during the Meccan period of Muhammad's life. According to Ibn Ishaq, Muhammad's tribe, the powerful Quraysh, were greatly concerned about their tribesman who had started claiming prophethood and wished to consult the Jewish rabbis' superior knowledge of the scriptures and about the prophets of God. The two Quraysh men described their tribesman, Muhammad, to the Jewish scholars. The rabbis told the men to ask Muhammad three questions:

text: They (the rabbis) said, 'Ask him about three things which we will tell you to ask and if he answers them then he is a Prophet who has been sent (by Allah); if he does not, then he is saying things that are not true, in which case how you will deal with him will be up to you. Ask him about some young men in ancient times, what was their story? For theirs is a strange and wondrous tale. Ask him about a man who travelled a great deal and reached the east and the west of the earth. What was his story? And ask him about the Ruh (soul or spirit) —what is it? If he tells you about these things, then he is a Prophet, so follow him, but if he does not tell you, then he is a man who is making things up, so deal with him as you see fit.'[18]

text: The famous story in the Sira relates that when Muhammad was informed of the three questions from the Rabbis, he declared that he would have the answers in the morning. However, Muhammad did not give the answer in the morning. For fifteen days, Muhammad did not answer the question. Doubt in Muhammad began to grow amongst the people of Mecca. Then, after fifteen days, Muhammad received the revelation that is Sura Al-Kahf ("The Cave"), the eighteenth chapter of the Quran. Surah Al-Kahf mentions the "People of the Cave," a strange story about some young men in ancient times who slept in a cave for many years (which is identical to the Syriac Christian myth of the Seven Sleepers Ephesus). Surah Al-Kahf also mentions the winds (related to the word for spirit, verse 45). Finally, the surah also mentions "a man who travelled a great deal and reached the east and the west of the earth"—namely, Dhul-Qarnayn. Though Ibn Ishaq himself does not explicitly mention the name Alexander, he relates that a storyteller told him that Dhul-Qarnayn was a Greco-Egyptian (an accurate description of Alexander):

text: A man who used to purvey stories of the foreigners, which were handed down among them, told me that Dhul-Qarnayn was an Egyptian whose name was Marzuban bin Mardhaba, the Greek.[19]

text: Ibn Ishaq's original work is lost, but it has been almost completely incorporated in Ibn Hisham (?–833 AD), another early Muslim historian. Ibn Hisham collected Ibn Ishaq's Sira and added his notes to it; in regards to Dhul-Qarnayn, Ibn Hisham noted:

text: Dhu al-Qarnain is Alexander the Greek, the king of Persia and Greece, or the king of the east and the west, for because of this he was called Dhul-Qarnayn [meaning, 'the two-horned one']...[verification needed]

text: The theme, amongst Islamic scholars, of identifying Dhul-Qarnayn with Alexander the Great appears to have originated here. Why Ibn Hisham made this identification is not entirely clear.

text: Pre-Islamic Arabic poetry[edit]

text: Ibn Ishaq recorded many pre-Islamic Arabic poems in the Sira, including a poem about Dhul-Qarnayn that he claims was composed by a pre-Islamic king of ancient Yemen named Tub'a Abu Kariba As'ad (Tub'a is commonly cited as the first of several kings of Arabia to convert to Judaism):

text: Dhu’l-Qarnayn before me was a Muslim

text:
Conquered kings thronged his court,
East and west he ruled, yet he sought
Knowledge true from a learned sage.
He saw where the sun sinks from view
In a pool of mud and fetid slime
Before him Bilqis [Queen of Sheba] my father's sister

text: The poem's reference to "a learned sage" from whom Dhul-Qarnayn sought knowledge from may be a reference to the story of Dhul-Qarnayn and Al-Khidir. Other pre-Islamic Arab poems about Dhul-Qarnayn are also reported in the Sira literature:

text: The pre-Islamic poet Al-`Asha and the contemporary of Muhammad Hassan ibn Thabit (?-674 AD) both composed verses referring to the conquest of Gog and Magog and furthest east by Dhu`l-qarnain.[12]

text: One poem by Hassan ibn Thabit reads:

text:
Ours the realm of Dhu 'l-Qarnayn the glorious
Realm like his was never won by mortal king.
Followed he the Sun to view its setting
When it sank into the somber ocean-spring;
Up he clomb to see it rise at morning,
From within its Mansions when the East it fired;
All day long the horizons led him onward,
All night through he watched the stars and never tired.
Then of iron and of liquid metal
He prepared a rampart not to be o'erpassed,
Gog and Magog there he threw in prison
Till on Judgement Day they shall awake at last[21]

text: Tafsir[edit]

text: Alexander is mentioned in the tafsir, the exegesis or commentaries of the Quran that were written by prominent early Islamic scholars. Significantly, Alexander the Great is mentioned in Tafsir al-Jalalayn, a well-known Sunni tafsir of the Quran from the 15th century. The tafsir notes that Dhul-Qarnayn's name was Alexander and also indicates that Dhul-Qarnayn was not a prophet:

text: And they, the Jews, question you concerning Dhū’l-Qarnayn, whose name was Alexander; he was not a prophet. Say: ‘I shall recite, relate, to you a mention, an account, of him’, of his affair.[22]

text: The commentators of the Quran debated on whether or not Dhul-Qarnayn was a prophet of Islam; some concluded that he was not a prophet but was a holy man or a "friend of God" since he is mentioned favorably in the Quran. In Islam it is ambiguous as to whether or not Dhul-Qarnayn is a full-fledged prophet.

text: Fakhr al-Din al-Razi (1149-1209 AD), in Tafsir al-Kabir also comments that Dhul-Qarnayn is Alexander the Macedonian. He provides a vague justification, saying that the Dhul-Qarnayn mentioned in the Quran traveled to the east and the west achieving victories and so he must be Alexander:

text: While a survey in the history we do not find anybody other than Macedonian Alexander, therefore, the Dhul Qarnayn is the same Macedonian Alexander.[23]

text: Other Islamic literature[edit]

text: Aristotelian Muslim philosophers, such as al-Kindi (801–873 AD), al-Farabi (872–950 AD), and Avicenna (980–1037 AD), enthusiastically embraced the concept of Dhul-Qarnayn being an ancient Greek king. They stylized Dhul-Qarnayn as a Greek philosopher king. Ibn Taymiyyah (1263–1328 AD) objected to the identification on the basis that Alexander was a pagan idolater, and he accused the Aristotelian Muslim philosophers such as Avicenna of making the "mistaken" identification:

text: ...Thus, the sages of the Persian Zoroastrians are all kafir [infidels], as well as the sages of Greece such as Aristotle and those like him. They were associationists, worshipping idols and the planets. Aristotle was before 'Isa (Jesus) by three hundred years, and was a minister for Alexander son of Phillip the Macedonian, who is mentioned in the histories of Rome and Greece, as well as the histories of the Christians and the Jews. He is not, however, the same as the man named Dhu-l-Qarnain who Allah mentioned in His book, as some imagined. Some people mistakenly thought that Aristotle was a minister for dhu-l-qarnain, when they saw that (the one found in the Western histories) was named Alexander, and the names are similar, they thought that they were one and the same man. This mistaken view has been promulgated by Ibn Seena [Avicenna] and some others with him.[24]

text: The Egyptian historian Al-Maqrizi (1364–1442 AD) claimed in his book Al-Khotatt that Dhul-Qarnayn was a Yemenite king named Sa'b and wrote:

text: Those who claim that he [Dhul-Qarnayn] was Iranian, Roman, or that he was Alexander of Macedon, are wrong.[verification needed]

text: The mystic Ibn Arabi (d. 638⁄1240) allegorically interpreted the figure of Dhul-Qarnayn as the heart which controls the left and right sides of the body.[2]

text: In recent times, Abdullah Yusuf Ali (1872–1953 AD) supported the notion of Dhul-Qarnayn being Alexander the Great and he indicated an extensive knowledge of the legends concerning Alexander:

text: Another suggestion was made that, Quranic Zul-qarnain was an ancient king of Persia. A king of Persia is referred to as a Ram with two horns in the Book of Daniel (viii. 3) in the Old Testament. But in the same Book, the Ram with the two horns was smitten, cast down to the ground, and stamped upon by a he-goat with one horn (8:7–8). But there is nothing in our literature to suggest that Zul-qarnain came to any such ignominious end. ... If it is argued that it was some old prehistoric Persian king who built the Iron Gates (18:96) to keep out the Gog and Magog tribes (18:94), this is no identification at all. ...

text: Another suggestion made is that it was some old prehistoric Himyarite king from Yemen, about whom nothing else is known. This, again, is no identification at all. ...

text: Personally, I have not the least doubt that Zul-Qarnain is meant to be Alexander the Great, the historic Alexander, and not the legendary Alexander...[25]

text: In his commentary of the Quran, Abul Ala Maududi (1903–1979 AD) noted that historically most Muslim scholars had endorsed the identification of Dhul-Qarnayn with Alexander the Great, but recent commentators have forwarded an alternative theory that Dhul-Qarnayn is Cyrus the Great:

text: The identification of Zul-Qarnain has been a controversial matter from the earliest times. In general the commentators have been of the opinion that he was Alexander the Great but the characteristics of Zul-Qarnain described in the Quran are not applicable to him. However, now the commentators are inclined to believe that Zul-Qarnain was Cyrus, an ancient king of Iran. We are also of the opinion that probably Zul-Qarnain was Cyrus, but the historical facts, which have come to light up to this time, are not sufficient to make any categorical assertion.[26]

text: Philological evidence[edit]

text: Philologists, studying ancient Christian legends about Alexander the Great, have come to conclude that the Quran's stories about Dhul-Qarnayn closely parallel certain legends about Alexander the Great found in ancient Hellenistic and Christian writings. There is some numismatic evidence, in the form of ancient coins, to identify the Arabic epithet "Dhul-Qarnayn" with Alexander the Great.[27] Finally, ancient Christian Syriac and Ethiopic manuscripts of the Alexander romance from the Middle East have been found which closely resemble the story in the Quran. This leads to the theologically controversial conclusion that Quran refers to Alexander in the mention of Dhul-Qarnayn.

text: The two-horned one[edit]

text: Silver tetradrachmon (ancient Greek coin) issued in the name of Alexander the Great, depicting Alexander with the horns of Ammon-Ra (242/241 BC, posthumous issue). Displayed at the British Museum.

tag: ul

text: The literal translation of the Arabic phrase "Dhul-Qarnayn," as written in the Quran, is "the Two-Horned." Alexander the Great was portrayed with two horns in ancient Greek depictions of Alexander:

text: It is well known that already in his own time Alexander was portrayed with horns according to the iconography of the Egyptian god Ammon.[28]

text: The Egyptian god Ammon-Ra was depicted with ram horns. Rams were considered a symbol of virility due to their rutting behavior. The horns of Ammon may have also represented the East and West of the Earth, and one of the titles of Ammon was "the two-horned." Alexander was depicted with the horns of Ammon as a result of his conquest of ancient Egypt in 332 BC, where the priesthood received him as the son of the god Ammon, who was identified by the ancient Greeks with Zeus, the King of the Gods. The combined deity Zeus-Ammon was a distinct figure in ancient Greek mythology. According to five historians of antiquity (Arrian, Curtius, Diodorus, Justin, and Plutarch), Alexander visited the Oracle of Ammon at Siwa in the Libyan desert and rumors spread that the Oracle had revealed Alexander's father to be the deity Ammon, rather than Philip.[27][29][30] Alexander styled himself as the son of Zeus-Ammon and even demanded to be worshiped as a god:

text: He seems to have become convinced of the reality of his own divinity and to have required its acceptance by others ... The cities perforce complied, but often ironically: the Spartan decree read, 'Since Alexander wishes to be a god, let him be a god.' [31]

text: Ancient Greek coins, such as the coins minted by Alexander's successor Lysimachus (360–281 BC), depict the ruler with the distinctive horns of Ammon on his head. Archaeologists have found a large number of different types of ancients coins depicting Alexander the Great with two horns.[27][32] The 4th century BC silver tetradrachmon ("four drachma") coin, depicting a deified Alexander with two horns, replaced the 5th century BC Athenian silver tetradrachmon (which depicted the goddess Athena) as the most widely used coin in the Greek world. After Alexander's conquests, the drachma was used in many of the Hellenistic kingdoms in the Middle East, including the Ptolemaic kingdom in Alexandria. The Arabic unit of currency known as the dirham, known from pre-Islamic times up to the present day, inherited its name from the drachma. In the late 2nd century BC, silver coins depicting Alexander with ram horns were used as a principal coinage in Arabia and were issued by an Arab ruler by the name of Abi'el who ruled in the south-eastern region of the Arabian Peninsula.[33]

text: In 1971, Ukrainian archeologist B.M. Mozolevskii discovered an ancient Scythian kurgan (burial mound) containing many treasures. The burial site was constructed in the 4th century BC near the city of Pokrov and is given the name Tovsta Mohyla (another name is Babyna Mogila). Amongst the artifacts excavated at this site were four silver gilded phalera (ancient Roman military medals). Two of the four medals are identical and depict the head of a bearded man with two horns, while the other two medals are also identical and depict the head of a clean-shaven man with two horns. According to a recent theory, the bearded figure with horns is actually Zeus-Ammon and the clean-shaved figure is none other than Alexander the Great.[34]

text: Alexander has also been identified, since ancient times, with the horned figure in the Old Testament in the prophecy of Daniel 8 who overthrows the kings of Media and Persia. In the prophecy, Daniel has a vision of a ram with two long horns and verse 20 explains that "The ram which thou sawest having two horns is the kings of Media and Persia.":

text: Josephus [37–100 AD], in his Antiquities of the Jews xi, 8, 5 tells of a visit that Alexander is purported to have made to Jerusalem, where he met the high priest Jaddua and the assembled Jews, and was shown the book of Daniel in which it was prophesied that some one of the Greeks would overthrow the empire of Persia. Alexander believed himself to be the one indicated, and was pleased. The pertinent passage in Daniel would seem to be VIII. 3–8 which tells of the overthrow of the two-horned ram by the one-horned goat, the one horn of the goat being broken in the encounter ...The interpretation of this is given further ... "The ram which thou sawest that had the two horns, they are the kings of Media and Persia. And the rough he-goat is the king of Greece." This identification is accepted by the church fathers ...[35]

text: The Christian Syriac version of the Alexander romance, in the sermon by Jacob of Serugh, describes Alexander as having been given two horns of iron by God. The legend describes Alexander (as a Christian king) bowing himself in prayer, saying:

text: O God ... I know in my mind that thou hast exalted me above all kings, and thou hast made me horns upon my head, wherewith I might thrust down the kingdoms of the world...I will magnify thy name, O Lord, forever ... And if the Messiah, who is the Son of God [Jesus], comes in my days, I and my troops will worship Him...[35]

text: In Christian Alexander legends written in Ethiopic (an ancient South Semitic language) between the 14th and the 16th century, Alexander the Great is always explicitly referred to using the epithet the "Two Horned." A passage from the Ethiopic Christian legend describes the Angel of the Lord calling Alexander by this name:

text: Then God, may He be blessed and exalted! put it into the heart of the Angel to call Alexander 'Two-horned,' ... And Alexander said unto him, ' Thou didst call me by the name Two-horned, but my name is Alexander ... and I thought that thou hadst cursed me by calling me by this name.' The angel spake unto him, saying, 'O man, I did not curse thee by the name by which thou and the works that thou doest are known. Thou hast come unto me, and I praise thee because, from the east to the west, the whole earth hath been given unto thee ...'[35]

text: References to Alexander's supposed horns are found in literature ranging many different languages, regions and centuries:

text: The horns of Alexander ... have had a varied symbolism. They represent him as a god, as a son of a god, as a prophet and propagandist of the Most High, as something approaching the role of a messiah, and also as the champion of Allah. They represent him as a world conqueror, who subjugated the two horns or ends of the world, the lands of the rising and of the setting sun ...[35]

text: For these reasons, among others, the Quran's Arabic epithet "Dhul-Qarnayn," literally meaning "the two-horned one," is interpreted as a reference to Alexander the Great.

text: Alexander's Wall[edit]

text: The Quran's story describes Dhul-Qarnayn building a great barrier in order to enclose the nations of Gog and Magog who "do great mischief in the earth." A similar story about Alexander is found in the Alexander romance and the origins of the story can be dated as far back as 329 BC.[citation needed]

text: Early accounts of Alexander's Wall[edit]

text: The building of gates in the Caucasus Mountains by Alexander to repel the barbarian peoples identified with Gog and Magog has ancient provenance and the wall is known as the Gates of Alexander or the Caspian Gates. The name Caspian Gates originally applied to the narrow region at the southeast corner of the Caspian Sea, through which Alexander actually marched in the pursuit of Bessus in 329 BC, although he did not stop to fortify it. It was transferred to the passes through the Caucasus, on the other side of the Caspian, by the more fanciful historians of Alexander. The Jewish historian Flavius Josephus (37–100 AD) mentions that:

text: ...a nation of the Alans, whom we have previously mentioned elsewhere as being Scythians ... travelled through a passage which King Alexander [the Great] shut up with iron gates.[36]

text: Josephus also records that the people of Magog, the Magogites, were synonymous with the Scythians.[37] According to Andrew Runni Anderson,[38] this merely indicates that the main elements of the story were already in place six centuries before the Quran's revelation, not that the story itself was known in the cohesive form apparent in the Quranic account. Similarly, St. Jerome (347–420 AD), in his Letter 77, mentions that,

text: The hordes of the Huns had poured forth all the way from Maeotis (they had their haunts between the icy Tanais and the rude Massagetae, where the gates of Alexander keep back the wild peoples behind the Caucasus).[39]

text: In his Commentary on Ezekiel (38:2), Jerome identifies the nations located beyond the Caucasus mountains and near Lake Maeotis as Gog and Magog. Thus the Gates of Alexander legend was combined with the legend of Gog and Magog from the Book of Revelation. It has been suggested that the incorporation of the Gog and Magog legend into the Alexander romance was prompted by the invasion of the Huns across the Caucasus mountains in 395 AD into Armenia and Syria.[40]

text: Alexander's Wall in Christian legends[edit]

text: Christian legends speak of the Caspian Gates (Gates of Alexander), also known as Alexander's wall, built by Alexander the Great in the Caucasus mountains. Several variations of the legend can be found. In the story, Alexander the Great built a gate of iron between two mountains, at the end of the Earth, to prevent the armies of Gog and Magog from ravaging the plains. The Christian legend was written in Syria shortly before the Quran's writing and closely parallels the story of Dhul-Qarnayn.[41] The legend describes an apocryphal letter from Alexander to his mother, wherein he writes:

text: I petitioned the exalted Deity, and he heard my prayer. And the exalted Deity commanded the two mountains and they moved and approached each other to a distance of twelve ells, and there I made ... copper gates 12 ells broad, and 60 ells high, and smeared them over within and without with copper ... so that neither fire nor iron, nor any other means should be able to loosen the copper; ... Within these gates, I made another construction of stones ... And having done this I finished the construction by putting mixed tin and lead over the stones, and smearing .... over the whole, so that no one might be able to do anything against the gates. I called them the Caspian Gates. Twenty and two Kings did I shut up therein.[42]

text: These pseudepigraphic letters from Alexander to his mother Olympias and his tutor Aristotle, describing his marvellous adventures at the end of the World, date back to the original Greek recension α written in the 4th century in Alexandria. The letters are "the literary expression of a living popular tradition" that had been evolving for at least three centuries before the Quran was written.[6]

text: Medieval accounts of Alexander's Wall[edit]

text: Several historical figures, both Muslim and Christian, searched for Alexander's Gate and several different identifications were made with actual walls. During the Middle Ages, the Gates of Alexander story was included in travel literature such as the Travels of Marco Polo (1254–1324 AD) and the Travels of Sir John Mandeville. The Alexander romance identified the Gates of Alexander, variously, with the Pass of Dariel, the Pass of Derbent, the Great Wall of Gorgan and even the Great Wall of China. In the legend's original form, Alexander's Gates are located at the Pass of Dariel. In later versions of the Christian legends, dated to around the time of Emperor Heraclius (575–641 AD), the Gates are instead located in Derbent, a city situated on a narrow strip of land between the Caspian Sea and the Caucasus mountains, where an ancient Sassanid fortification was mistakenly identified with the wall built by Alexander. In the Travels of Marco Polo, the wall in Derbent is identified with the Gates of Alexander. The Gates of Alexander are most commonly identified with the Caspian Gates of Derbent whose thirty north-looking towers used to stretch for forty kilometers between the Caspian Sea and the Caucasus Mountains, effectively blocking the passage across the Caucasus.[43] Later historians would regard these legends as false:

text: The gate itself had wandered from the Caspian Gates to the pass of Dariel, from the pass of Dariel to the pass of Derbend [Derbent], as well as to the far north; nay, it had travelled even as far as remote eastern or north-eastern Asia, gathering in strength and increasing in size as it went, and actually carrying the mountains of Caspia with it. Then, as the full light of modern day come on, the Alexander Romance ceased to be regarded as history, and with it Alexander's Gate passed into the realm of fairyland.[44]

text: In the Muslim world, several expeditions were undertaken to try to find and study Alexanders's wall, specifically the Caspian Gates of Derbent. An early expedition to Derbent was ordered by the Caliph Umar (586–644 AD) himself, during the Arab conquest of Armenia where they heard about Alexander's Wall in Derbent from the conquered Christian Armenians. Umar's expedition was recorded by the renowned exegetes of the Quran, Al-Tabarani (873–970 AD) and Ibn Kathir (1301–1373 AD), and by the Muslim geographer Yaqut al-Hamawi (1179–1229 AD):

text: ... Umar sent ... in 22 A.H. [643 AD] ... an expedition to Derbent [Russia] ... `Abdur Rahman bin Rabi`ah [was appointed] as the chief of his vanguard. When 'Abdur Rehman entered Armenia, the ruler Shehrbaz surrendered without fighting. Then when `Abdur Rehman wanted to advance towards Derbent, Shehrbaz [ruler of Armenia] informed him that he had already gathered full information about the wall built by Dhul-Qarnain, through a man, who could supply all the necessary details ...[45]

text: Two hundred years later, the Abbasid Caliph Al-Wathiq (?–847 AD) dispatched an expedition to study the wall of Dhul-Qarnain in Derbent, Russia. The expedition was led by Sallam-ul-Tarjuman, whose observations have were recorded by Yaqut al-Hamawi and by Ibn Kathir:

text: ...this expedition reached ... the Caspian territory. From there they arrived at Derbent and saw the wall [of Dhul-Qarnayn].[46]

text: The Muslim geographer Yaqut al-Hamawi further confirmed the same view in a number of places in his book on geography; for instance under the heading "Khazar" (Caspian) he writes:

text: This territory adjoins the Wall of Dhul-Qarnain just behind Bab-ul-Abwab, which is also called Derbent.[46]

text: The Caliph Harun al-Rashid (763 – 809 AD) even spent some time living in Derbent. Not all Muslim travelers and scholars, however, associated Dhul-Qarnayn's wall with the Caspian Gates of Derbent. For example, the Muslim explorer Ibn Battuta (1304–1369 AD) traveled to China on order of the Sultan of Delhi, Muhammad bin Tughluq and he comments in his travel log that "Between it [the city of Zaitun in Fujian] and the rampart of Yajuj and Majuj [Gog and Magog] is sixty days' travel."[47] The translator of the travel log notes that Ibn Battuta confused the Great Wall of China with that supposedly built by Dhul-Qarnayn.[48]

text: Gog and Magog[edit]

text: In the Quran, it is none other than the Gog and Magog people whom Dhul-Qarnayn has enclosed behind a wall, preventing them from invading the Earth. In Islamic eschatology, before the Day of Judgement Gog and Magog will destroy this gate, allowing them to ravage the Earth, as it is described in the Quran:

text: Gog and Magog in Christian legends[edit]

text: In the Syriac Christian legends, Alexander the Great encloses the Gog and Magog horde behind a mighty gate between two mountains, preventing Gog and Magog from invading the Earth. In addition, it is written in the Christian legend that in the end times God will cause the Gate of Gog and Magog to be destroyed, allowing the Gog and Magog horde to ravage the Earth;

text: The Lord spake by the hand of the angel, [saying] ...The gate of the north shall be opened on the day of the end of the world, and on that day shall evil go forth on the wicked ... The earth shall quake and this door [gate] which thou [Alexander] hast made be opened ... and anger with fierce wrath shall rise up on mankind and the earth ... shall be laid waste ... And the nations that is within this gate shall be roused up, and also the host of Agog and the peoples of Magog [Gog and Magog] shall be gathered together. These peoples, the fiercest of all creatures.[42]

text: The Christian Syriac legend describes a flat Earth orbited by the sun and surrounded by the Paropamisadae (Hindu Kush) mountains. The Paropamisadae mountains are in turn surrounded by a narrow tract of land which is followed by a treacherous Ocean sea called Okeyanos. It is within this tract of land between the Paropamisadae mountains and Okeyanos that Alexander encloses Gog and Magog, so that they could not cross the mountains and invade the Earth. The legend describes "the old wise men" explaining this geography and cosmology of the Earth to Alexander, and then Alexander setting out to enclose Gog and Magog behind a mighty gate between a narrow passage at the end of the flat Earth:

text: The old men say, "Look, my lord the king, and see a wonder, this mountain which God has set as a great boundary." King Alexander the son of Philip said, "How far is the extent of this mountain?" The old men say, "Beyond India it extends in its appearance." The king said, "How far does this side come?" The old men say, "Unto all the end of the earth." And wonder seized the great king at the council of the old men ... And he had it in his mind to make there a great gate. His mind was full of spiritual thoughts, while taking advice from the old men, the dwellers in the land. He looked at the mountain which encircled the whole world ... The king said, "Where have the hosts [of Gog and Magog] come forth to plunder the land and all the world from of old?" They show him a place in the middle of the mountains, a narrow pass which had been constructed by God ...[42]

text: Flat Earth beliefs in the Early Christian Church varied and the Fathers of the Church shared different approaches. Those of them who were more close to Aristotle and Plato's visions, like Origen, shared peacefully the belief in a spherical Earth. A second tradition, including St Basil and St Augustine, accepted the idea of the round Earth and the radial gravity, but in a critical way. In particular they pointed out a number of doubts about the antipodes and the physical reasons of the radial gravity. However, a flat Earth approach was more or less shared by all the Fathers coming from the Syriac area, who were more inclined to follow the letter of the Old Testament. Diodore of Tarsus (?–390 AD), Cosmas Indicopleustes (6th century), and Chrysostom (347–407 AD) belonged to this flat Earth tradition.[43][49][50]

text: Medieval accounts of Gog and Magog[edit]

text: In the Christian Alexander romance literature, Gog and Magog were sometimes associated with the Khazars, a Turkic people who lived near the Caspian Sea. In his 9th century work Expositio in Matthaeum Evangelistam, the Benedictine monk Christian of Stavelot refers to the Khazars as Hunnic descendants of Gog and Magog, and says they are "circumcised and observing all [the laws of] Judaism";[51] the Khazars were a Central Asian people with a long association with Judaism. A Georgian tradition, echoed in a chronicle, also identifies the Khazars with Gog and Magog, stating they are "wild men with hideous faces and the manners of wild beasts, eaters of blood."[52]

text: Early Muslim scholars writing about Dhul-Qarnayn also associated Gog and Magog with the Khazars. Ibn Kathir (1301–1373 CE), the famous commentator of the Quran, identified Gog and Magog with the Khazars who lived between the Black and Caspian Sea in his work Al-Bidayah wa al-Nihayah (The Beginning and the End).[53][54] The Muslim explorer Ahmad ibn Fadlan, in his travelogue regarding his diplomatic mission in 921 AD to Volga Bulgars (a vassal of the Khazarian Empire), noted the beliefs about Gog and Magog being the ancestors of the Khazars.[55]

text: Thus Muslim scholars associated the Khazars with Dhul-Qarnayn just as the Christian legends associated the Khazars with Alexander the Great.

text: The rising place of the Sun[edit]

text: This section relies too much on references to primary sources. Please improve this section by adding secondary or tertiary sources. (April 2013) (Learn how and when to remove this template message)

text: A peculiar aspect of the story of Dhul-Qarnayn, in the Quran, is that it describes Dhul-Qarnayn travelling to "the rising place of the Sun" and the "setting place of the Sun," where he saw the Sun sets into a murky (or boiling) spring of water (or mud). Dhul-Qarnayn also finds a people living by the "rising place of the Sun," and finds that these people somehow have "no shelter."

text: In his commentary of the Quran, Ibn Kathir (1301–1373 CE) explains that verse 18:89 is referring to the furthest point that could be travelled west:

text: (Until, when he reached the setting place of the sun,) means, he followed a route until he reached the furthest point that could be reached in the direction of the sun's setting, which is the west of the earth. As for the idea of his reaching the place in the sky where the sun sets, this is something impossible, and the tales told by storytellers that he traveled so far to the west that the sun set behind him are not true at all. Most of these stories come from the myths of the People of the Book [Jews and Christians] and the fabrications and lies of their heretics.[56]

text: In this commentary Ibn Kathir differentiates between the end of the (presumably flat) Earth and the supposed "place in the sky" where the sun sets (the "resting place" of the sun. Ibn Kathir contends that Dhul-Qarnayn did reach the farthest place that could be travelled west but not the "resting place" of the sun and he goes on to mention that the People of the Book (Jews and Christians) tell myths about Dhul-Qarnayn travelling so far beyond the end of the Earth that the sun was "behind him." This shows that Ibn Kathir was aware of the Christian legends and it suggests that Ibn Kathir considered Christian myths about Alexander to be referring to the same figure as the Dhul-Qarnayn mentioned in the Qu'an.

text: A similar theme is elaborated upon in several places in the Islamic hadith literature, in Sahih al-Bukhari and Sahih Muslim:

text: It is narrated ... that the Messenger of Allah one day said: Do you know where the sun goes? They replied: Allah and His Apostle know best. He (the Holy Prophet) observed: Verily it (the sun) glides till it reaches its resting place under the Throne [of Allah]. Then it falls prostrate and remains there until it is asked: Rise up and go to the place whence you came, and it goes back and continues emerging out from its rising place...[57]

text: The setting place of the sun is also commented on by Al-Tabari (838-923 AD) and Al-Qurtubi (1214–1273 AD) and, like Ibn Kathir, they showed some reservations towards the literal idea of the sun setting in a muddy spring but held to the basic theme of Dhul-Qarnayn reaching the ends of the Earth. The later Islamic scholar Imam al-Suyuti (1445–1505 AD) also maintained that the Earth is flat.[citation needed]

text: That the Earth must be spherical was known since at least the time of Pythagoras (570–495 BC), but this knowledge did not reach ancient folklore such as the Alexander romance where Alexander travels to the ends of a flat Earth. It is notable that, unlike the Babylonians, Greeks, and Indians, the pre-Islamic Arabs had no scientific astronomy. Their knowledge of astronomy was limited to measuring time based on empirical observations of the "rising and setting" of the sun, moon, and particular stars. This area of astronomical study was known as anwa and continued to be developed after Islamization by the Arabs.[58] Astronomy in medieval Islam began in the 8th century and the first major Muslim work of astronomy was Zij al-Sindh written in 830 by al-Khwarizmi. The work is significant as it introduced the Ptolemaic system into Islamic sciences (the Ptolemaic system was ultimately replaced by the Copernican system during the Scientific Revolution in Europe).

text: The rising place of the Sun in the Alexander legends[edit]

text: Rendition of Homer's view of the world (prior to 900 BC). The Homeric conception of the world involved a flat, circular Earth, surrounded by mountains and by Oceanus, the world-ocean of classical antiquity, considered to be an enormous river encircling the world. The Sun emerges from underneath the Earth, traveling along the fixed dome of the sky, and is shown rising from Oceanus.

text: The place of his [the Sun's] rising is over the sea, and the people who dwell there, when he is about to rise, flee away and hide themselves in the sea, that they be not burnt by his rays; and he passes through the midst of heaven to the place where he enters the window of heaven; and wherever he passes there are terrible mountains, and those who dwell there have caves hollowed out in the rocks, and as soon as they see the Sun passing [over them], men and birds flee away from before him and hide in the caves ... And when the Sun enters the window of heaven, he [it] straight away bows down and makes obeisance before God his Creator; and he travels and descends the whole night through the heavens, until at length he finds himself where he [the Sun] rises ... So the whole camp mounted, and Alexander and his troops went up between the fetid sea and the bright sea to the place where the Sun enters the window of heaven; for the Sun is the servant of the Lord, and neither by night nor by day does he cease from his travelling.[42]

text: The Christian legend is much more detailed than the Quran's version and elaborates at length about the cosmology of the Earth that is implied by the story:

text: He [Alexander] said to them [the nobles]: "This thought has arisen in my mind, and I am wondering what is the extent of the earth, and how high the heavens are ... and upon what the heavens are fixed ... Now this I desire to go and see, upon what the heavens rest, and what surrounds all creation." The nobles answered and said to the king, ... "As to the thing, my lord, which thy majesty desires to go and see, namely, upon what the heaveans rest, and what surrounds the earth, the terrible seas which surround the world will not give thee a passage; because there are eleven bright seas, on which the ships of men sail, and beyond these there is about ten miles of dry land, and beyond these ten miles there is the foetid sea, Okeyanos (the Ocean), which surrounds all creation. Men are not able to come near to this foetid sea ... Its waters are like poison and if men swim therein, they die at once."[42]

text: This ancient motif of a legendary figure traveling to the end of Earth is also found in the Epic of Gilgamesh, which can be dated to c. 2000 BC, making it one of the earliest known works of literary writing.[59] In the epic poem, in tablet nine, Gilgamesh sets out on a quest for the Water of Life to seek immortality. Gilgamesh travels far to the east, to the mountain passes at the ends of the earth where he grapples and slays monstrous mountain lions, bears and others. Eventually he comes to the twin peaks of Mount Mashu at the end of the earth, from where the sun rises from the other world, the gate of which is guarded by two terrible scorpion-beings. They allow him to proceed through the gate after Gilgamesh convinces them to let him pass, stating his divinity and desperation, and he travels through the dark tunnel where the sun travels every night. Just before the sun is about to catch up with him, and with the North Wind and ice lashing him, he reaches the end. The world at the end of the tunnel is a bright wonderland full of trees with leaves of jewels. The 17th chapter of the apocryphal Book of Enoch describes a journey to the far west where the fire of the west receives every setting of the sun and a river of fire empties into the great western sea.[60] Chapters 72–80 describe the risings and settings of the sun through 12 portals of heaven in the east and west.[61] The myth of a flat Earth surrounded by an Ocean into which the sun sets is also found in the Iliad, the famous epic poem written by Homer and dated to c. 900 BC. The story of creation in the Hebrew Bible, in Genesis 1:10, (dated c. 900–550 BC) is also considered by scholars to be describing a flat Earth surrounded by a sea.[62]

text: The ancient Greek historian Herodotus (484–425 BC) also gave an account of the eastern "end of the Earth," in his descriptions of India. He reported that in India the sun's heat is extremely intense in the morning, instead of noon being the hottest time of day. It has been argued that he based this on his belief that since India is located at the extreme east of a flat Earth, it would only be logical if the morning were unbearably hot due to the sun's proximity.[63]

text: Alexander's travels[edit]

text: The Quran and the Alexander romance both have it that Dhul-Qarnayn (or Alexander) travelled a great deal. In the Quran's story of Dhul-Qarnayn, "God gave him unto every thing a road" (or more literally, "We gave him the means of everything" 18:84) He travels as far as the ends of the Earth, to the place on the Earth where the Sun sets (the west) and the place on the Earth where the Sun rises (the east). The Quran portrays him traveling to the "setting of the sun." Muslim interpretations of these verses are varied, but classical Muslim scholars seemed to have been of the opinion that Dhul-Qarnayn's journey was real, not allegorical, and that Dhul-Qarnayn's wall is also a real, physical wall somewhere on Earth.

text: In the Christian legends, Alexander travels to the places of the setting and rising of the Sun and this is meant to say that he traveled to the ends of the flat Earth and thus he had traversed the entire world. This legendary account served to convey the theme of Alexander's exploits as a great conqueror. Alexander was indeed a great conqueror, having ruled the largest empire in ancient history by the time he was 25 years old. However, the true historical extent of Alexander's travels are known to be greatly exaggerated in legends. For example, legend has it that upon reaching India,

text: ... said Alexander 'Truly, then, all the inhabited world is mine. West, north, east, south, there is nothing more for me to conquer.' Then he sat down and wept because there were not other worlds for him to conquer.[64]

text: In reality, while Alexander did travel a great deal, he did not travel further west than ancient Libya and did not travel further east than the fringes of India. According to historians, Alexander invaded India following his desire to reach the "ends of the world and the Great Outer Sea." However, when he reached the Hyphasis River in the Punjab in 326 BC, his army nearly mutinied and refused to march further east, exhausted by years of campaigning. Alexander's desire to reach "the ends of the Earth" was instilled by his tutor Aristotle:

text: Alexander derived his concept of `Asia' from the teaching of Aristotle, for whom `the inhabited earth' was surrounded by `the Great sea' Ocean, and was divided into three areas – `Europe, Libya and Asia.' Thus the earth was not round but flat, and `Asia' was limited on the west by the Tanais (Don), the inland sea and the Nile, and on the east by `India' and `the Great Sea' ... he was mistaken in supposing that from the ridge of the Paropamisadae (Hindu Kush) one would see `the outer sea' and that `India' was a small peninsula running east into that sea.[65]

text: This view of the world taught by Aristotle and followed by Alexander is apparent in Aristotle's Meteorologica, a treatise on earth sciences where he discusses the "length" and "width" of "the inhabited earth." However, Aristotle knew that the Earth is spherical and even provided observational proof of this fact. Aristotle's cosmological view was that the Earth is round but he prescribed to the notion of an "inhabited Earth," surrounded by the Ocean, and an "uninhabited Earth" (though exactly how much of this was understood by his student Alexander the Great is not known).

text: Al-Khidir[edit]

text: Surah Al-Kahf has also been linked to the Alexander romance through a second story. The Quran verses 18:60–82, which immediately precede the story of Dhul-Qarnayn, mention the story of Al-Khidir and a fish that miraculously comes to life. It has been theorized that the Quran's story was influenced by the story of the Water of Life (Fountain of Youth) mentioned in Eastern versions of the Alexander romance.[66]

text: In some Islamic traditions, Al-Khidir (literally "the Green One," an enigmatic figure in Islam) is the cousin or servant of Alexander or Dhul-Qarnayn.[citation needed] There are several versions of the Persian Alexander Romance in which Al-Khiḍr figures as a servant of Dhul-Qarnayn or Alexander the Great. In one version, Al-Khidr and Dhul-Qarnayn cross the Land of Darkness to find the Water of Life. Dhul-Qarnayn gets lost looking for the spring, but Khiḍr finds it and gains eternal life. In the Iskandarnamah by an anonymous author, Khiḍr is asked by Dhul-Qarnayn to lead him and his armies to the Water of Life.[67] Khidr agrees, and eventually stumbles upon the Water of Life on his own.[68]

text: The Quran's story is about Moses and Al-Khidir, though the classical Islamic scholars showed some disagreement over whether or not 'Moses' in this story is Moses of the Israelites. In the Quran's story, this Moses goes with a servant ( identified as Joshua in Hadith) to the "junction of the two seas". A certain fish (which they presumably had been carrying with them) "in an amazing way" makes its way to the sea. When the servant tells Moses this, they retrace their steps. They then meet one of God's servants (traditionally called Al-Khidir, although not named in the Quran) who puts Moses to a test of patience in which Moses must travel with Al-Khidir but not ask any questions. Al-Khidir cracks a hole in a vessel endangering its passengers, then he murders a boy, and then rebuilding a wall each time causing Moses to break his silence. Al-Khidir explains how each of his lawless acts was for a greater good and Moses fails the test of patience. The Quranic story is remarkably similar to Jewish folklore concerning Elijah. In the Jewish tale, Rabbi Joshua ben Levi asks to join the prophet Elijah in his wanderings. Elijah grants the Rabbi's wish on the condition that he refrain from asking any questions about any of the prophet’s actions. He agrees and they begin their journey. Elijah carries out "lawless" acts, like Al-Khidir in the Quran, and similarly the Rabbi breaks his silence and demands an explanation.

text: The story in the Quran is summarized in a hadith of Sahih Al-Bukhari:

text: Allah revealed to him [Moses]: 'At the junction of the two seas there is a slave of Ours [Al-Khidir] who is more learned than you. ' Moses asked, 'O my Lord, how can I meet him?' Allah said, 'Take a fish and put it in a basket (and set out), and where you, will lose the fish, you will find him.' So Moses (took a fish and put it in a basket and) set out, along with his boy-servant Yusha' bin Nun, till they reached a rock (on which) they both lay their heads and slept. The fish moved vigorously in the basket and got out of it and fell into the sea and there it took its way through the sea (straight) as in a tunnel.[69]

text: The idea that the sources of these verses are found in the Alexander romance was first proposed by Mark Lidzbarski and Karl Duroff in 1892. In 1913 Israel Friedlander wrote a book on the subject titled`"The Al-Khidir Legend and the Alexander Romance." Early Persian and Ethiopic Muslim legends concerning Alexander made a similar connection between Al-Khidir and Alexander (see figure).[70]

text: One similarity between the Quran story and the Alexander romance concerns the fish that miraculously comes to life. This motif is found in the Syriac sermon by Jacob of Serugh, where Alexander travels in search of the Water of Life (Fountain of Youth). A shorter version of the story in also found in the Greek β-recension of the Alexander romance. In the Syriac legend, Alexander finds a wise man who tells Alexander to take a salted fish and wash it in the fountains in the Land of Darkness, and if the fish comes to life then he will have found the Water of Life:

text: The king [Alexander] said, "I have heard that therein [in the Land of Darkness] is the fountain of life, And I desire greatly to go forth and see if, of a truth, it is [there]. The old man said, ... "Command thy cook take with him a salt fish, and wherever he sees a fountain of water let him wash the fish; And if it be that it comes to life in his hands when he washes it, That is the fountain of the water of life which thou askest for, O King."[42]

text: Another similarity between the Al-Khidir legends and the Alexander romance is the Water of Life. Though the Quran does not mention the Fountain of Youth, it is alluded to in the hadith literature. Al-Khidir in the hadith literature is described as being immortal, having taught every prophet before Muhammad, and having the appearance of a young adult but having a long, white beard, and he is even described as being present at Muhammad's funeral:

text: ... whether Khidr was still alive, was a more contentious issue. In the twelfth century a Hanbali scholar denied the continued existence of Khidr. The majority of scholars, on the other hand, affirmed Khidr’s eternal life and have continued to do so into the twentieth century. New Arabic texts on Khidr have appeared during the last twenty years of the twentieth century, the majority of which have rejected the idea of his eternal life as ‘unislamic’ without enlisting new arguments for their viewpoint though.[71]

text: The story of Al-Khidir, in the Quran, does not mention Dhul-Qarnayn, rather only a figure called "Moses" is referred to by name. This would seem to shed doubt on the idea that the story is about Dhul-Qarnayn, as it appears to be a story about Moses of the Israelites. However, the early Islamic literature raises questions about whether the Moses mentioned in the story of the fish is the Moses of the Israelites, or someone entirely different:

text: Narrated Sa'id: Ibn 'Abbas said, "Ask me (any question)" I [Sa'id] said, "O Abu Abbas! ... There is a man at Kufa who is a story-teller called Nauf; who claims that he (Al-Khadir's companion) is not Moses of Bani Israel ... Ibn 'Abbas said, "(Nauf) the enemy of Allah told a lie."[72]

text: The story, in the Alexander romance[59] and in the Quran, is considered by scholars to have been influenced by the Epic of Gilgamesh (specifically Giglamesh's search for the Water of Life ). Gilgamesh reaches the water but, like Alexander, fails to become immortal. Like Alexander, Giglamesh also comes to the spot at which the sun rises from the Earth:

text: The sources of the Khidir-story go back to mythological motifs appearing in the Akkadian Epic of Gilgamesh, in the Alexander romance and in Jewish legends centered around the mythical figure of Elijah. The story as it is told by the Quran interweaves several narrative motifs: the test of patience, the quest for the spring of life, and so on. The identification of the servant of god with al-Khidir is attested to in traditions from the Prophet, which may be the reason why it is rarely contested by Muslim commentators. There is less exegetical unanimity about whether the Moses mentioned here is the Egyptian Moses or not.[73]

text: A peculiar aspect of the story in the Quran is that Al-Khidir is found at a distant place called the "junction of the two seas." This is believed by secular scholars to be a reference to the end of the World, where the sun rises from the outer Ocean sea. The "junction of the two seas" is mentioned in several places in the Quran:

text: He [Allah] is the one who has let free the two bodies of flowing water, one sweet and palatable, and the other salty and bitter. And He has made between them a barrier and a forbidding partition. (Quran 25:53)

text: This has been compared to the ancient Akkadian myth of the Abzu, the name for a fresh water underground sea that was given a religious quality in Sumerian and Akkadian mythology. Lakes, springs, rivers, wells, and other sources of fresh water were thought to draw their water from the Abzu underground sea, while the Ocean that surrounded the world was a saltwater sea. This underground sea is called Tehom in the Hebrew Bible. For example, Genesis 49:25 says, "blessings of the heavens above, and Tehom lying beneath".[74] Wensinck explains, "Thus it appears that the idea of there being a sea of sweet water under our earth, the ancient Tehom, which is the source of springs and rivers, is common to the Western Semites".[75] These two bodies of water are also depicted as deities in the Babylonian creation myth, the Enûma Elish, where Abzu is deity of the freshwater ocean and Tiamat is the deity of the salt water ocean. The Enuma Elish begins:

text: When above the heavens did not yet exist nor the earth below, Apsu the freshwater ocean was there, the first, the begetter, and Tiamat, the saltwater sea, she who bore them all; they were still mixing their waters, and no pasture land had yet been formed, nor even a reed marsh...

text: Similarly in Greek mythology, the world was surrounded by Oceanus, the world-ocean of classical antiquity. Oceanus was personified as the god Titan, whose consort was the aquatic sea goddess Tethys.[76] It was also thought that rainfall was due a third ocean above the "Firmament of the Sky" (a vast reservoir above the firmament of the sky is also described in the Genesis creation narrative). A comprehensive understanding of the Earth's water cycle did not exist until the "Origins of Springs" was written by Pierre Perrault in 1674 AD.

text: Islamic depictions of Alexander the Great[edit]

text: Arabic traditions[edit]

text: Alexander the Great features prominently in early Arabic literature. There are many surviving versions of the Alexander romance in Arabic that were written after the conquest of Islam. It is also thought that pre-Islamic Arabic versions of the Alexander romance may have existed.[77]

text: The earliest surviving Arabic narrative of the Alexander romance was composed by Umara ibn Zayd (767–815 AD). In the tale, Alexander travels a great deal, builds the Wall against Gog and Magog, searches for the Water of Life (Fountain of Youth), and encounters angels who give him a "wonder-stone" that both weighs more than any other stone but is also as light as dust. This wonder-stone is meant to admonish Alexander for his ambitions and indicate that his lust for conquest and eternal life will not end until his death. The story of the wonder-stone is not found in the Syriac Christian legend, but is found in Jewish Talmudic traditions about Alexander as well as in Persian traditions.[12][78]

text: A South Arabian Alexander legend was written by the Yemenite traditionist Wahb ibn Munabbih (?–732 AD) and this legend was later incorporated in a book by Ibn Hisham (?–833 AD) regarding the history of the Himyarite Kingdom in ancient Yemen. In the Yemenite variation, Dhul-Qarnayn is identified with an ancient king of Yemen named Tubba', rather than Alexander the Great, but the Arabic story still describes the story of Alexander's Wall against Gog and Magog and his quest for the Water of Life. The story also mentions that Dhul-Qarnayn (Tubba') visited a castle with glass walls and visited the Brahmins of India. The South Arabian legend was composed within the context of the division between the South Arabs and North Arabs that began with the Battle of Marj Rahit in 684 AD and consolidated over two centuries.[12]

text: The Alexander romance also had an important influence on Arabic wisdom literature. In Secretum Secretorum ("Secret of Secrets", in Arabic Kitab sirr al-asrar), an encyclopedic Arabic treatise on a wide range of topics such as statecraft, ethics, physiognomy, alchemy, astrology, magic and medicine, Alexander appears as a speaker and subject of wise sayings and as a correspondent with figures such as Aristotle. The origins of the treatise are uncertain. No Greek original exists, though there are claims in the Arabic treatise that it was translated from the Greek into Syriac and from Syriac into Arabic by a well-known 9th century translator, Yahya ibn al-Bitriq (?–815 AD). It appears, however, that the treatise was actually composed originally in Arabic.

text: In another example of Arabic wisdom literature relating to Alexander, Ibn al-Nadim (?–997 AD) refers to a work on divination titled The Drawing of Lots by Dhul-Qarnain and to a second work on divination by arrows titled The gift of Alexander, but only the titles of these works have survived.

text: Notably, the Abbasid Caliph Al-Mu'tasim (794–842 AD) had ordered the translation of the Thesaurus Alexandri, a work on elixirs and amulets, from Greek and Latin into Arabic. The Greek work Thesaurus Alexandri was attributed to Hermes (the great messenger of the gods in Greek mythology) and similarly contained supposed letters from Aristotle addressed to Alexander.[12][79]

text: A more direct Arabic translation of the Alexander romance, called Sirat Al-Iskandar, was discovered in Constantinople, at the Hagia Sophia, and is dated to the 13th century. This version includes the letter from Alexander to his mother about his travels in India and at the end of the World. It also includes features which occur exclusively in the Syriac version. Interestingly, the Arabic legend also retains certain pagan elements of the story, which are sometimes modified to suit the Islamic message:

text: It is quite remarkable that some characteristics belonging to a pre-Islamic 'pagan' entourage, have survived in the text ... For example, Alexander orders an offering of sacrificial animals at the temple of Hercules. In the Arabic letter the name of the deity has been replaced by Allah ... Another passage in the account of the palace of Shoshan or Sus, gives a description of the large silver jars, which were alleged to have capacity of three hundred and sixty measures of wine. Alexander puts this assertion to the test, having one of the jars filled with wine and poured out for his soldiers during a banquet. This exact specification has been maintained, heedless of the Islamic ban on the use of wine ... These retouched borrowings are highly significant in this text, because the Arabic Alexander figure is portrayed as a propagator of Islamic monotheism.[77]

text: Another piece of Arabic Alexander literature is the Laments (or Sayings) of the Philosophers. These are a collection of remarks supposedly made by some philosophers gathered at the tomb of Alexander after his death. This legend was originally written in the 6th century in Syriac and was later translated into Arabic and expanded upon. The Laments of the Philosophers eventually gained enormous popularity in Europe:[8]

text: [The 'Sayings of the Philosophers' are] remarks of the philosophers gathered at the tomb of Alexander, who utter a series of apophthegms on the theme of the brevity of life and the transience of human achievement ... a work entitled 'Sayings of the Philosophers' was first composed in Syriac in the sixth century; a longer Arabic version was composed by Hunayan Ibn Ishaq (809-973) the distinguished scholar-translator, and a still longer one by al-Mubashshir ibn Fatiq (who also wrote a book about Alexander) around 1053. Hunayan's version was translated into Spanish ... in the late thirteenth century.[80]

text: The Arabic Alexander romance also had an influence on a wider range of Arabic literature. It has been noted that some features of the Arabic Alexander legends found their way into The Seven Voyages of Sinbad the Sailor, a medieval story-cycle of Arabic origin. Sinbad, the hero of the epic, is a fictional sailor from Basrah, living during the Abbasid Caliphate. During his voyages throughout the seas east of Africa and south of Asia, he has fantastic adventures going to magical places, meeting monsters, and encountering supernatural phenomena. As a separate example of this influence on Arabic literature, the legend of Alexander's search for the Water of Life is found in One Thousand and One Nights, a collection of Middle Eastern and South Asian stories and folktales compiled in Arabic during the Islamic Golden Age.[12]

text: Andalusian traditions[edit]

text: After the Umayyad Muslim conquest of Al-Andalus (Spain) in 711 AD, Muslim literature flourished under the Caliphate of Córdoba (929 to 1031 AD). An Arabic derivative of the Alexander romance was produced, called Qisas Dhul-Qarnayn (Tales of Dhul-Qarnayn).[10] The material was later incorporated into Qisas Al-Anbiya (Tales of the Prophets):

text: By the turn of the first millennium C.E., the romance of Alexander in Arabic had a core centered on the Greek legendary material ... Interwoven later into this narrative in the Tales of the Prophets literature were episodes of an apparent Arab-Islamic elaboration: the construction of a great barrier to keep the people of Gog and Magog from harassing the people of the civilized world until Judgement Day, the voyage to the end of the Earth to witness the sun set in a pool of boiling mud, and Dhu al-Qarnayn's expedition into the Land of Darkness in search of the Fountain of Life accompanied by his companion Khidir ("the Green-One").[11]

text: By 1236 AD, the Reconquista was essentially completed and Europeans had retaken the Iberian peninsula from the Muslims, but the Emirate of Granada, a small Muslim vassal of the Christian Kingdom of Castile, remained in Spain until 1492 AD. During the Reconquista, Muslims were forced to either convert to Catholicism or leave the peninsula. The descendants of Muslims who converted to Christianity were called the Moriscos (meaning "Moor-like") and were suspecting of secretly practicing Islam. The Moriscos used a language called Aljamiado, which was a dialect of the Spanish language (Mozarabic) but was written using the Arabic alphabet. Aljamiado played a very important role in preserving Islam and the Arabic language in the life of the Moriscos; prayers and the sayings of Muhammad were translated into Aljamiado transcriptions of the Spanish language, while keeping all Quranic verses in the original Arabic. During this period, a version of the Alexander legend was written in the Aljamaido language, building on the Arabic Qisas Dhul-Qarnayn legends as well as Romance language versions of the Alexander romance.[81][82]

text: New Persian traditions[edit]

text: With the Muslim conquest of Persia in 644 AD, the Alexander romance found its way into Persian literature—an ironic outcome considering pre-Islamic Persia's hostility towards the national enemy who conquered the Achaemenid Empire and was directly responsible for centuries of Persian domination by Hellenistic foreign rulers. However, he is not depicted as a warrior and conqueror, but as a seeker of truth who eventually finds the Ab-i Hayat (Water of Life).[83] Islamic Persian accounts of the Alexander legend, known as the Iskandarnamah, combined the Pseudo-Callisthenes material about Alexander, some of which is found in the Quran, with indigenous Sassanid Middle Persian ideas about Alexander. For example, Pseudo-Callisthenes is the source of many incidents in the Shahnama written by Ferdowsi (935–1020 AD) in New Persian. Persian sources on the Alexander legend devised a mythical genealogy for him whereby his mother was a concubine of Darius II, making him the half-brother of the last Achaemenid shah, Darius. By the 12th century such important writers as Nizami Ganjavi (from Ganja, Azerbaijan) were making him the subject of their epic poems. The Muslim traditions also elaborated the legend that Alexander the Great had been the companion of Aristotle and the direct student of Plato.

text: There is also evidence that the Syriac translation of the Alexander romance, dating to the 6th century, was not directly based on the Greek recensions but was based on a lost Pahlavi (pre-Islamic Persian) manuscript.[77]

text: Central Asian traditions[edit]

text: Certain Muslim people of Central Asia, specifically Bulgar, Tatar and Bashkir peoples of the Volga-Ural region (within what is today Tatarstan in the Russian Federation), carried on a rich tradition of the Alexander legend well into the 19th century. The region was conquered by the Abbasid Caliphate in the early 10th century. In these legends, Alexander is referred to as Iskandar Dhul-Qarnayn (Alexander the Two Horned), and is "depicted as founder of local cities and an ancestor of local figures." The local folklore about Iskandar Dhul-Qarnayn played in an important role in communal identity:

text: The conversion of the Volga Bulghars to Islam is commonly dated to the first decades of the 10th century, and by the middle of the 12th century, it is apparent that Islamic historical figures and Islamic forms of communal validation had become important factors for Bulghar communal and political cohesion. The Andalusian traveler Abū Hamid al-Gharnāti who visited Bulghar in the 1150s, noted that Iskandar Dhūl-Qarnayn passed through Bulghar, that is, the Volga-Kama region, on his way to build the iron walls that contained Yā'jūj and Mā'jūj [Gog and Magog] within the land of darkness ... while Najib al-Hamadāni reports that the rulers of Bulghar claimed descent from Iskandar Dhūl-Qarnayn.[84]

text: The Iskandar Dhul-Qanryan legends played an important role in the conversion narrative of the Volga Bulgar Muslims:

text: There are numerous digressions dealing with the founding of the Bulghar conversion narrative, and legends concerning Iskandar Dhūl-Qarnayn [Alexander Dhul-Qarnayn] and Socrates. According to the account, Socrates was born a Christian in Samarqand and went to Greece to serve Iskandar Dhūl-Qarnayn (Iskandar Rūmi). Together, they went to the Land of Darkness (diyār-i zulmat) to seek the Fountain of Youth (āb-i hayāt). In the northern lands they built a city and called it Bulghar.[84]

text: In 1577 AD the Tsardom of Russia annexed control of the region and Bulgar Muslim writings concerning Dhul-Qarnayn do not appear again until the 18th and 19th centuries, which saw a resurgence of local Iskandar Dhul-Qarnayn legends as a source of Muslim and ethnic identity:

text: It was only at the turn of the 18th and 19th centuries that we begin to see historical legends concerning Iskandar Dhūl-Qarnayn reemerge among Volga-Kama Muslims, at least in written form, and it was not until the 19th century that such legends were recorded from local Muslim oral tradition. In one of his earliest historical works, entitled Ghilālat al-Zamān and written in 1877 the Tatar theologian, Shihāb al-Dīn Marjānī wrote that according to Arabic and other Muslim writings, as well as according to popular legends, the city of Bulghar was founded by Alexander the Great.[84]

text: Orientalist and western views[edit]

text: In the 19th century, Orientalists studying the Quran began researching the identity of Dhul-Qarnayn. Theodor Nöldeke, believed that Dhul-Qarnayn was none other than Alexander the Great as mentioned in versions of the Alexander romance and related literature in Syriac (a dialect of Middle Aramaic).[85] The Syriac manuscripts were translated into English in 1889 by E. A. Wallis Budge.[42]

text: In the early 20th century Andrew Runni Anderson wrote a series of articles on the question in the Transactions of the American Philological Association.[35] The findings of the philologists imply that the source of the Quran's story of Dhul-Qarnayn is the Alexander romance, a thoroughly embellished compilation of Alexander's exploits from Hellenistic and early Christian sources, which underwent numerous expansions and revisions for two-thousand years, throughout Antiquity and the Middle Ages.[86]

text: As can be seen in the following quotation from Edwards, secular philologists studying ancient Syriac Christian legends about Alexander the Great also came to the conclusion that Dhul-Qarnayn is an ancient epithet for Alexander the Great. Edwards says,

text: Alexander's association with two horns and with the building of the gate against Gog and Magog occurs much earlier than the Quran and persists in the beliefs of all three of these religions [Judaism, Christianity and Islam]. The denial of Alexander's identity as Dhul-Qarnain is the denial of a common heritage shared by the cultures which shape the modern world—both in the east and the west. The popularity of the legend of Alexander the Great proves that these cultures share a history which suggests that perhaps they are not so different after all.[86]


document_title: Mass-to-charge ratio

question_text: who determined the mass to charge ratio of an electron

text: Mass-to-charge ratio

text: Origin[edit]

text: When charged particles move in electric and magnetic fields the following two laws apply:

text:
F

=
Q
(

E

+

v

×

B

)
,

{\displaystyle \mathbf {F} =Q(\mathbf {E} +\mathbf {v} \times \mathbf {B} ),}

(Lorentz force law)

F

=
m

a

=
m

d

v

d

t

{\displaystyle \mathbf {F} =m\mathbf {a} =m{\frac {\mathrm {d} \mathbf {v} }{\mathrm {d} t}}}

(Newton's second law of motion)

text: where F is the force applied to the ion, m is the mass of the particle, a is the acceleration, Q is the electric charge, E is the electric field, and v × B is the cross product of the ion's velocity and the magnetic flux density.

text: This differential equation is the classic equation of motion for charged particles. Together with the particle's initial conditions, it completely determines the particle's motion in space and time in terms of m/Q. Thus mass spectrometers could be thought of as "mass-to-charge spectrometers". When presenting data in a mass spectrum, it is common to use the dimensionless m/z, which denotes the dimensionless quantity formed by dividing the mass number of the ion by its charge number.[1]

text: Combining the two previous equations yields:

text: This differential equation is the classic equation of motion of a charged particle in vacuum. Together with the particle's initial conditions it determines the particle's motion in space and time. It immediately reveals that two particles with the same m/Q ratio behave in the same way. This is why the mass-to-charge ratio is an important physical quantity in those scientific fields where charged particles interact with magnetic or electric fields.

text: Exceptions[edit]

text: There are non-classical effects that derive from quantum mechanics, such as the Stern–Gerlach effect that can diverge the path of ions of identical m/Q.

text: Symbols and units[edit]

text: The IUPAC recommended symbol for mass and charge are m and Q, respectively,[3][4] however using a lowercase q for charge is also very common. Charge is a scalar property, meaning that it can be either positive (+) or negative (−). The Coulomb (C) is the SI unit of charge; however, other units can be used, such as expressing charge in terms of the elementary charge (e). The SI unit of the physical quantity m/Q is kilograms per coulomb.

text: Mass spectrometry and m/z[edit]

text: The units and notation above are used when dealing with the physics of mass spectrometry; however, the m/z notation is used for the independent variable in a mass spectrum.[5] This notation eases data interpretation since it is numerically more related to the unified atomic mass unit.[1] The m refers to the molecular or atomic mass number and z to the charge number of the ion; however, the quantity of m/z is dimensionless by definition.[5] An ion of 100 atomic mass units (m = 100) carrying two charges (z = 2) will be observed at m/z = 50.

text: History[edit]

text: In the 19th century, the mass-to-charge ratios of some ions were measured by electrochemical methods. In 1897, the mass-to-charge ratio of the electron was first measured by J. J. Thomson.[6] By doing this, he showed that the electron was in fact a particle with a mass and a charge, and that its mass-to-charge ratio was much smaller than that of the hydrogen ion H+. In 1898, Wilhelm Wien separated ions (canal rays) according to their mass-to-charge ratio with an ion optical device with superimposed electric and magnetic fields (Wien filter). In 1901 Walter Kaufman measured the increase of electromagnetic mass of fast electrons (Kaufmann–Bucherer–Neumann experiments), or relativistic mass increase in modern terms. In 1913, Thomson measured the mass-to-charge ratio of ions with an instrument he called a parabola spectrograph.[7] Today, an instrument that measures the mass-to-charge ratio of charged particles is called a mass spectrometer.

text: Charge-to-mass ratio[edit]

text: The charge-to-mass ratio (Q/m) of an object is, as its name implies, the charge of an object divided by the mass of the same object. This quantity is generally useful only for objects that may be treated as particles. For extended objects, total charge, charge density, total mass, and mass density are often more useful.

text: Derivation:

text:
q
v
B
=
m
v

v
r

{\displaystyle qvB=mv{\frac {v}{r}}}

 or

q
m

=

v

B
r

{\displaystyle {\frac {q}{m}}={\frac {v}{Br}}}

 (1)

text:
Since

F

e
l
e
c
t
r
i
c

=

F

m
a
g
n
e
t
i
c

{\displaystyle F_{electric}=F_{magnetic}}

,

text:
E
q
=
B
q
v

{\displaystyle Eq=Bqv}

 or

v
=

E
B

{\displaystyle v={\frac {E}{B}}}

 (2)

text: Equations (1) and (2) yield

text:
q
m

=

E

B

2

r

{\displaystyle {\frac {q}{m}}={\frac {E}{B^{2}r}}}

text: Significance[edit]

text: In some experiments, the charge-to-mass ratio is the only quantity that can be measured directly. Often, the charge can be inferred from theoretical considerations, so that the charge-to-mass ratio provides a way to calculate the mass of a particle.

text: Often, the charge-to-mass ratio can be determined from observing the deflection of a charged particle in an external magnetic field. The cyclotron equation, combined with other information such as the kinetic energy of the particle, will give the charge-to-mass ratio. One application of this principle is the mass spectrometer. The same principle can be used to extract information in experiments involving the cloud chamber.

text: The ratio of electrostatic to gravitational forces between two particles will be proportional to the product of their charge-to-mass ratios. It turns out that gravitational forces are negligible on the subatomic level, due to the extremely small masses of subatomic particles.

text: The electron[edit]

text:
The elementary charge-to-electron mass quotient,

e

/

m

e

{\displaystyle e/m_{e}}

, is a quantity in experimental physics. It bears significance because the electron mass me is difficult to measure directly, and is instead derived from measurements of the elementary charge e and

e

/

m

e

{\displaystyle e/m_{e}}

. It also has historical significance; the Q/m ratio of the electron was successfully calculated by J. J. Thomson in 1897—and more successfully by Dunnington, which involves the angular momentum and deflection due to a perpendicular magnetic field. Thomson's measurement convinced him that cathode rays were particles, which were later identified as electrons, and he is generally credited with their discovery.

text:
The 2014 CODATA recommended value is

e

/

m

e

{\displaystyle e/m_{e}}

 = 2988824117997600000♠−1.758820024(11)×1011 C/kg.[2] CODATA refers to this as the electron charge-to-mass quotient, but ratio is still commonly used.

text: There are two other common ways of measuring the charge-to-mass ratio of an electron, apart from Thomson and Dunnington's methods.

text:
The Magnetron Method: Using a GRD7 Valve (Ferranti valve),[dubious – discuss] electrons are expelled from a hot tungsten-wire filament towards an anode. The electron is then deflected using a solenoid. From the current in the solenoid and the current in the Ferranti Valve, e/m can be calculated.[citation needed]
Fine Beam Tube Method: A heater heats a cathode, which emits electrons. The electrons are accelerated through a known potential, so the velocity of the electrons is known. The beam path can be seen when the electrons are accelerated through a helium (He) gas. The collisions between the electrons and the helium gas produce a visible trail. A pair of Helmholtz coils produces a uniform and measurable magnetic field at right angles to the electron beam. This magnetic field deflects the electron beam in a circular path. By measuring the accelerating potential (volts), the current (amps) to the Helmholtz coils, and the radius of the electron beam, e/m can be calculated.[8]

tag: ol

text: Zeeman Effect[edit]

text: The charge-to-mass ratio of an electron may also be measured with the Zeeman effect, which gives rise to energy splittings in the presence of a magnetic field B:

text: Here mj are quantum integer values ranging from -j to j, with j as the eigenvalue of the total angular momentum operator J, with[2]

text: where S is the spin operator with eigenvalue s and L is the angular momentum operator with eigenvalue l. gJ is the Landé g-factor, calculated as

text: The shift in energy is also given in terms of frequency ν and wavelength λ as

text: Measurements of the Zeeman effect commonly involve the use of a Fabry–Pérot interferometer, with light from a source (placed in a magnetic field) being passed between two mirrors of the interferometer. If δD is the change in mirror separation required to bring the mth-order ring of wavelength λ + Δλ into coincidence with that of wavelength λ, and ΔD brings the (m + 1)th ring of wavelength λ into coincidence with the mth-order ring, then

text: It follows then that

text: Rearranging, it is possible to solve for the charge-to-mass ratio of an electron as